Light-projecting device



F. w. DRESSEL LIGHT PROJECTING DEVICE Aug. 28, 1928.

Filed May 1924 2 Sheets-Sheet M ATTORNEY Aug. 28, 1928. 1,682,608

F. w. DRESSEL LIGHT PROJECTING DEVICE Filed May 1924 2 Sheets-Sheet 2 j z J9 3 58 6.3

/ Unix I 4 41 5 r z i I i i l i g 1 f. I I '40 41 INVENTOR fiederz'af Wire?! ATTORNEY Patented Aug". 28, 1928.

UNITED STATES PATENT OFFICE.

FREDERICK W. DRESSEL, OF NEW YORK, N. Y., ASSIGNOR TO DRESSEL RAILWAY LAMP & SIGNAL CORPORATION, OF ARLINGTON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

LIGHT-YROJECTING DEVIC'E.

Application filed May 1, 1924. Serial No. 710,217.

My present invention relates more particularly to light projecting devices of the type in which a light concentrator such as a lens or a reflector having a more or less definite focus is used to concentrate a more or less definite beam in any desired direction and is particularly applicable where the concentrator is rigidly mounted in normally fixed position, and the direction and concentration of the beam being adjusted by adjustment of the lamp bulb or other source of light.

The specific purpose in view has been to provide a locomotive head light wherein the concentrating reflector that projects the beam may be rigidly fixed with reference to the lo comotive, while the support for the light is provided with simple adjusting means where by it may be displaced from the exact ocus of the reflector an amount sufficient to direct the beam upward, downward or sidewise. as Well as to concentrate or expand it within the narrow limits necessary for use on a lo com otive: also to provide the adjusting means in such rigid construction and with such socure locking means that the vibration of the locomotive cannot operate to cause objectionable vibration of the light bulb nor to change the adjustments. It will be evident. however. that certain features of the invention are ap plicable to light concentrating projectors designed or used for other purposes.

The present embodiment of my invention involves mounting the light bulb in a socket securely supported independently of the reflector and to provide a hole in the apex of the reflector large enough to permit bodily movements of the socket and the bulb carried thereby to the extent necessary for the purposes above described.

One feature of my invention consists in rendering the lamp bulb universally adj ustable within the limits necessary, by means located on an independent socket support. H has been common to provide such sockets with screw means for fore and aft adjustment: of the light bulb in the axis of the projector for the purpose of causing the projected beams to diverge much or little or to be nearly parallel or to cross, and I may provide my de vice with an axially adjustable socket not materially difier nt from those now in use.

For my purposes, however, the socket is mounted upon a standard having a fine vertieal adjustment and including means for securely locking the same in any adjusted position. This standard and its adjusting means are swiveled in a suitable support for limited rotary adjustment of the socket in a horizontal plane, and including means for securely locking the standard against rotary displacement from its adjusted position. i

The primary vertical adjustment of the socket is axial, while the primary horizontal adjustment is circular so that the center of the bulb is adjustable in the surface of a single cylinder. However, the axis of such a cylinder is well behind the focal point of the reflector so that the surface of such a cylinder for the small area over which the light source is adjustable, does not vary materially from a true plane. Furthermore. if desired. the

axial adjustment of the socket member may be used to correct any such variation.

For a locomotive the beam may be directed downwardly so that its axis will center on the track one hundred yards or more ahead. although the axis of the head light itself is substantially horizontal. The right and left adjustment to center on the track is obvious. The above and other features of my inventi on will be more readily understood from the following detailed description in connection with the accompanying drawings, wherein.

Fig. 1 is a vertical section through a head light casing and reflector showing my improved lamp supporting means in operative position;

Fig. 2 is a view in rear elevation of the lamp supporting means;

Fig. 3 is a view in vertical section on the line 33 of Fig. 2; and

Fig. 4 is a view in transverse section on the line 44 of Fig. 2.

The light projector, as for instance a locomotive head light, is shown as comprising a cylindrical housing 10 supported upon feet or brackets 11.. The housing contains a lamp bulb 12, a light concentrator having a more or less definite focus such as a parabolic reflector 13 and a transparent closure 14, which maybe a lens or plane glass, as desired. A convenient means for mounting a glass reflector comprises a casting having a cylindrical portion'15 riveted within the forward end of the housing 10 and formed with an in ternal flange 16 to which the turned-back marginal edge 17 of a metallic supporting cup 18 is secured as by screws 18. The glass reflector 13 is approximately parabolic and has the usual reflecting material 19 on its rear face but a silver plated copper reflector may be used if desired. The reflector is clamped within the protective cup 18 by clamping ring 20, held by bolts 20. The window 14 is supported by front casing meniber 21 formed with an inwardly directed lip 22 cooperating with a removable clamping ring 23, all of said parts being carried by frame ring 21 and usually secured to housing 10 by a hinge and clamping fastener. These and other usual features such as the door in the side of the housing are not shown. since the construction thus far described is merely illustrative of what an ordinary locomotive head light may be.

For purposes of my invention, the openings 24 and 25 in the rear center of the refiector 13 and its protecting and supporting member 18, are substantially larger than the neck of the lamp 12 so as to permit a universal adjustment of the lamp whereby it may be displaced from the axis or from the focal center of the reflector. I

The lamp supporting and adjusting mechanism includes a horizontal socket member 2a carried at the upper end of a. vertically adjustable standard 27 swiveled in a hollow column 28 rising from a flat base 29.

Various expedients might be resorted to for securing the column in fixed position within the housing 10 but I prefer to firmly secure the base of the column upon a relatively wide platform member 31 of relatively thick-gauge metal, which extends across the bottom of the housing behind the reflector. Bolts or similar securing devices 32 secure the base to the platform member, which by virtue of its substantial nature and its rigid connection at each end to the housing, prevents vibration of the column.

The standard 27 has its lower portion formed as a cylinder fitting the cylindrical portion 28 of the hollow column 28 in which it is rotatable and axially slidable. The retary movement is limited by a spline screw 35 engaging the slot 34 which is of width slightly greater than the spline screw. The upper portion of standard 27 is formed with an enlarged screw threaded portion 33 engaging an internally threaded sleeve 48 which fits and is rotatable in an enlarged cylindrical recess 28* in column 28. It rests on a shoulder 47 and is secured against withdrawal by a screw 49 engaging an annular recess 50. The threaded sleeve 48 is rotated to raise or lower the standard. thereby raising or lowering the socket 26 the amount necessary for vertical adjustment of the lamp while swinging of the standard 27 within the limits permitted by keyway 34 afford the desired horizontal adjustment of the lamp.

Near its lower end and preferably opposite the set screw 35, the column 28 is formed with a cutaway portion leaving a substantially semicylindrical column section 36. Cooperating with this semicylindrical section is a con'iplcmentary clamping section 37. A vertically apcrtured car 38 at one end of the clamp 37 is pivoted on a pintle 39 dropped into aligned openings 40 in a pair of spaced lugs 41 extending laterally from the column above and below the cutaway portion thercof. At its opposite free end the clamping member carries a clamping screw 42 threaded in aperture 43 in a lug 44 integral with the column whereby member 37 may be clamped upon the standard to rigidly lock the same in desired adjusted position.

At a point slightly above the clamping member 37 the column is interiorly enlarged forming a. shoulder 45 and a space 46 (Fig. around the lower end 27 of the standard of sutlicient diameter to accommodate the enlarged threaded portion section 33 when the latter is adjusted downwardly.

The sleeve 48 is formed with a notched flange 51 by which it may be manually rotated to screw the standard vertically therethrough. After the desired axial adjustment of the standard has been accomplished, the set screw 49 may be tightened to lock the sleeve.

The rotary adjustment of the standard to swing the socket: member 26 to any desired angle may be eil'ectcd without disturbing the vertical adjustment of the socket member, by turning the sleeve 48 by which it is carried. Thus each adjustment is entirely independent of. and may be changed at any time without affecting the other.

To etl'cct axial shifting of the lamp relative to the socket member. I provide a rearward extension 54- of the cylindrical socket member 26, formed with an inturned car 55 having a threaded opening 56 therein. A hand screw 58 working in the threaded opening has threaded engagement with a lug 59 on the rear end of a sleeve 66 fitting and sliding within the socket member 26. Preferably the lag is formed with a threaded opening 61 therein receiving the reduced forward end (32 of the hand screw. In practice the threads of the main section of the. screw which works in the opening 56 and the threads of the reduced and 2 of the screw which works in the lug 59. are of reverse pitch so that comparativcly rapid axial shifting or sliding of the sleeve may be had upon turning the screw.

A locking nut 63 on the screw 58 serves to complementary member (not shown) carrying electrical conductors.

The manner of manually making the various adjustments for positioning the lamp 12 in any desired relation to the focal center of the reflector will be obvious from the above. Adjustment of the bulb in a vertical plane will regulate the vertical angle of the beam and thereby the distance ahead at which the main beam centers upon the ground. Lateral adjustment of the bulb will regulate the lateral direction of the beam, usually for centering it midway between the rails. Axial shifting of the bulb regulates the concentration or the expansion of the beam to control the area of the surface effectively illuminated and the brilliance of such illumination in the usual way. Theoretically this will be combined with a slight directional component when the bulb axis is at an angle to the reflector axis, but these adjustment angles are usually too small to be of much practical effect in this connection. As pointed out above, the reflecting means, whether it be of parabolic or other shape, is always fixed, while the light source is universally adjustable about the focal center of the reflector, or other concentrator.

One of the principal advantages of this invention from a practical standpoint is that the lamp can be reached and manually adjusted through the usual side door in the head light casing without disturbing any electrical connections and while the lamp is in operation so that light beam offers visible evidence of the correctness of the adjustments which are being made.

Various changes and alterations might be made in the general form and arrangement of the parts described without departing from the spirit of the invention or the scope of the appended claims.

Moreover, words such as vertical, horizontal, etc. are not intended as words of limitation but rather as a convenience in defining the relations of the respective adjustments to each other and to the axis of the reflector. For instance, except as concerns a locomotive head light, it will be evident that if the axis of the reflector be shifted to the vertical, what I have described above as vertical will become horizontal and the horizontal will become vertical yet the significant relations of the parts may remain precisely the same as before and clearly within the scope of my claims. It will be noted too that while there are certain advantages in having the lamp bulb project horizontally through a hole which symmetrically surrounds the axis of the projector, the device would still be operative for universal adjustment in the desired region about the focus of the projector even if the hole were more or less lateral and the bulb projecting therethrough at a corresponding angle to the projector axis.

I claim:

1. A head light, including a casing having a reflector of the beam projecting type with a hole in the rear end thereof, secured to said casing by its rim and a rigid base support secured to and extending vertically upward from the bottom portion of said casing and free from contact or connection with said reflector except by way of the casing and rim securing means, in combination with a lamp bulb and means for supporting it from said base and through said hole independently of said reflector, with its luminous element 10- catcd in focal regions within the reflector and its socket support outside of said reflector; said support being formed with means affording universal adjustment of said luminous element within said focal regions and means for rigidly locking the parts in the adjusted positions; said support means including a vertical standard and guide column therefor and an intermediate sleeve swiveled in the column and screw threaded about the standard for rotary and screw support thereof.

2. A locomotive head. light comprising a head light casing and a forwardly presented parabolic light reflector secured by its rim in said casing and having an axial opening in its rear end, in combination with means for adjustably supporting a lamp bulb with its neck portion extending through said opening, but without contact therewith, said means including a massive base, a tubular standard, a vertical shank rotatable in said standard, a clamp for locking said shank in any desired position of location, a screw nut swiveled in said support and screw threaded to said standard. said shank carrying at its upper end a horizontal slide, a carriage for a lamp socket slidable therein and a differential screw for endwise adjustment of said lamp socket carriage.

Signed at Arlington, in the county of Hudson, and State of New Jersey, this 30 day of April, A. D. 1924:.

FREDERICK W. DRESSEL. 

